A major use of natural benzaldehyde is as an ingredient in "natural" cherry flavor and other flavors for augmenting or enhancing the aroma or taste of consumable materials including foodstuffs, chewing gums, medicinal products, toothpastes, chewing tobacco, smoking tobacco and smoking tobacco articles.
A major use of natural acetaldehyde is as an ingredient in "natural" orange flavor and other flavors for augmenting or enhancing the aroma or taste of consumable materials including foodstuffs, chewing gums, medicinal products, toothpastes and chewing tobacco.
Natural benzaldehyde has been used in natural cherry flavors in the form of an apricot kernel derivative as is taught in U.S. Pat. No. 1,416,128 issued on May 16, 1922. An undesirable feature of the known processes for preparing natural benzaldehyde from apricot kernels or reground press cake is that along with the benzaldehyde, toxic hydrocyanic acid is produced which must be separated completely from the benzaldehyde and from the rest of the oil prior to use. Other techniques for producing natural benzaldehyde are known but these techniques produce it in such yields as to cause the resulting process to be uneconomical. For example, Hockenhull, et al, Biochem. J., 50, 605-9, (1952) (Title: "Oxidation of Phenylacetic Acid by Penicillium chrysogenum") discloses production of benzaldehyde starting with phenylacetic acid through either benzyl alcohol or mandelic acid via the sequences: ##STR2##
Towers, et al, Can. J. Zool. 1972, 50(7), 1047-50 ("Defensive secretion: biosynthesis of hydrogen cyanide and benzaldehyde from phenylalanine by a millipede") discloses a biosynthetic pathway for the production of benzaldehyde from dietary phenylalanine in Oxidus gracilis, thusly: ##STR3##
Halpin, et al, Biochemistry, 1981, Volume 20, pages 1525-1533 (Title: "Carbon-13 Nuclear Magnetic Resonance Studies of Mandelate Metabolism in Whole Bacterial Cells and in Isolated, in Vivo Cross-Linked Enzyme Complexes") discloses the biochemical pathway from mandelate ion to benzaldehyde, thusly: ##STR4##
Reeves, et al. TAPPI 48(2), pages 121-5, (1965) (Title: "Reaction Products Formed Upon the Alkaline Peroxide Oxidation of Lignin-Related Model Compounds") discloses the effect of alkaline hydrogen peroxide oxidation on cinnamaldehyde whereby the cinnamaldehyde is split at the double bond with the formation of the corresponding benzaldehyde and benzoic acid according to the reaction: ##STR5##
At pages 124, column 1, paragraph 1, Reeves, et al theorizes that a "reverse aldol reaction" is not responsible for the formation of vertraldehyde due to the fact that acetaldehyde the other product of the potential "reverse aldol reaction" was not obtained. Therefore, our discovery of the "retro-aldol" reaction taking place, to wit: ##STR6## was unexpected and unobvious. The "retro-aldol" reaction, to wit: ##STR7## indeed, took place due to the different reaction conditions from those proposed and set forth in Reeves, et al; different insofar as temperature of reaction and time of reaction are concerned; longer times of reaction and higher temperatures of reaction being the conditions in our "retro-aldol" reaction as opposed to shorter times of reaction and lower temperatures insofar as the Reeves, et al reaction is concerned.
In our own invention, no reagents other than base and naturally occurring cinnamaldehyde and solvent are utilized to carry out the "retro-aldol" reaction of our invention, to wit: ##STR8##
The process of our invention thus gives rise to unobvious, unexpected and advantageous results and represents an advance in the art in the production of "natural" benzaldehyde taken alone or in combination with natural cinnamaldehyde; and, further, in the production of "natural" acetaldehyde.